Lifting-jack



No. s|5,ao9. Patented Dem-ls, |898.

J. C. CUVERT. LIFTING JACK.

, Applica/cion' led Sept. 26, 1898.)

(No Model.)

Tu: mams PETERS co., mormujuo., WASHINGTON, uv c.

lUNITED STATES.V

PATENT OEEICE.

JAMES C. COVERT, OF WATERVLIEI, NEW YORK.

LIFTING-JACK.

SPECIFICATION forming part of Letters Patent No. 615,809, dated December13, 1898. Application filed September 26,1898.y Serial No. 691,926. v(Nomodel.)

To @ZZ whom it may concern.-

Beit known that I, JAMES C. COVERT, a citizen of the United States,residing at Watervliet, in the county of Albany and State of NewYork,have invented certain new and useful Improvements in Lifting-Jacks;and I do hereby declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and. use the same.

This invention relates to an improvement' in lifting-jacks, and moreparticularly in that part of the jack commonly known as the lifting barand its associated rest or bracket; and it is embodied in theconstruction and arrangement of parts hereinafter described, and definedin the claims.

The invention is designed :more particularly for use in connection withthat type of jack commonly known as a lever-liftingbar type; but Idesire it understood that the same is applicable or adapted for use withother types of jacks. j

Heretofore the step or rest of a lifting-bar has been adjustable up ordown either by a clutch connection or by 'having a series of teeth orindentations formed on one edge of the bar, against which a tooth orprojection on the rest engages. The objection to these various types andconstructions resides in the fact that the step when the jack itself issuddenly moved or jarred or turned from the proper upright positionbecomes disengaged, and the step, of its own weight falling down,therefore has to be raised when the jack is to used. To overcome theseobjections, frictionsprings have been employed, which are carried by thestep and rest against the bar, the friction being sufficient to preventthe jar from unseating the engaging parts and also preventing the stepfrom its own weight sliding down the bar. It will be appreciated thatwhen such springs are used it requires considerable force to adjust thestep, and, further, the constant frictional contact soon causes thesprings to wear away as the step is being adjusted. Another objection tothis type of spring-holding step is the necessary expense of equippingthe same with the bracket attachment of an open or bent-strip type asdistinguished from the cast type. The objection to the latter type isthat they are frequently broken and require a core when molding,increasing thereby largely the expense. The former type vis muchpreferred owing to the fact that it can be made of steel strips readilybent into proper shape andthe bar-openings punched, thereby forming avery strong, cheap, and comparatively light structure.

Further objects of my invention will be presently stated.

In the drawings I have shown the inven= tion as applied to the ordinarylever-and-bar jack for the purpose of illustration.

Figure 1 is an elevation of the jack having the improvement thereon.Fig. 2 is an enlarged detail view of the upper end of the lifting-barwith the rest or bracket portion applied to the same, the parts beingshown in section. Figs. 3 and 4 are cross-sections on the lines 3 3 and4 4 of Fig. 2.

In the drawings, A represents the base, A' the standard, B theactuating-lever, and B the fulcrum-link, of the jack proper. Y

C designates the vertically-movable lifting bar, which is convenientlyformed of metal and of oblong cross-section. On the forward edge of thelifting-bar is formed a series of elongated vertical depressions I), thelength of which is greater than the thickness of the material of thestep, presently to be referred to. The lower horizontal walls of thesedepressions are horizontal,while the upper walls are inclined. Thesedepressions are spaced in equal distance apart and extend for aconsiderable distance along the edge of the bar, the material leftbetween the depressions constituting What may be termed projections,teeth,7 or ledges, the outer faces being curved or rounded, as shown atd, while the bases d of the depressions D are flat, for pur posespresently to be stated. The opposite edge of the bar is formed with alike series of depressions D, with bases d", and consequent ledges orteeth. This series of depressions or ledges, however, extend from apoint below the plane of the uppermost depression to a point below thelowerin ost depression of the opposite side.

E designates a rest or step which is formed of a single piece of metal,conveniently of steel, having a lower horizontal portion e, an outeroblique portion e', and a relatively long upper horizontal portion e2,lying parallel with the horizontal portion e. Through the upper andlower portions of the step are formed elongated openings F F. The upwardopening has a squared or straight outer end wall f and a curved innerend wall f2, corresponding in curvature to the curvature of the teeth orledges of the bar. The lower opening is formed like that of the upperopening, but in a reverse manner-that is to say, the outer end wall f3is curved, while the inner end Wall f4 is straight. These openings arearranged with the outer end wall of the lower opening laterally beyondthe plane of the outer end wall of the upper opening, so that when therest is not in engagement in the depressions I) the step will be at anincline and when in engagement in the depressions the step will beperfectly horizontal. By this arrangement it will be seen that when thestep is adjusted to the various depressions the upper portions will havethe outer end wall of its opening brought in contact with the base ofthe depression D in which the same is placed, thereby moving the lowerface of the portion adjacent to the end wall against the straight faceof the tooth or projection immediately below. Vhen in this position, thestraight end wall of the lower opening of the rest is carried into thedepression on the opposite side of the bar, and the under face adjacentthereto rests against the upper face of the projections immediatelybelow. By this means it will be appreciated that when pressure isbrought against, the upper face of the step the tendency will be to drawthe upper straight wall closely into the depression and against the iiatbase thereof and to force the lower one into close engagement with thebase of its associated depression. This necessarily holds the stepfirmly in position. I-Ieretofore in this class of step when the pressurehas been brought to bear on the upper horizontal portion the pressureusually tends to bend the portion downward, thereby making the stepuseless, for the reason that the relative positions of the parts aredisar'ranged, and it is impossible to properly regulate or move thestep.

By the construction above described it will be seen that both the upperand lower portions of the step are independently supported by therespective projections and any bendling or disarran ging of parts isprevented,

and when it is desired to lower the step it is only necessary to tiltthe toe or point upward and forceit inward, and by a reverse movement ofthe lower portion thus carries the curved end walls into engagement withthe bar, and owing to their curvature they are prevented from enteringinto the grooves or depressions and are allowed to slide easily andreadily over the teeth or projections. It will be seen also that in thisconstruction it is practically impossible to jar or cause the rest orbracket to move downward without assisting it by taking hold of samewith the hand and adjusting the parts yas above described. lVhen it isdesired to move the step upward, the same can be done withoutpreliminary adjustment, owing to the inclination of the lower sides ofthe teeth or projections.

By actual test and use I have found by the construction above describedthat the objections to the prior-known devices are entirely overcome.

It will be observed that the edge of the lifting-bar adjacent to thesupporting portion of the step will endanger the breaking of the paintor inarring the iinish of its axle by rea.- son of the teeth orprojections. To avoid this, I secure to the upper face of the rest orbracket a leather strip F, securely fastened to the step in anyconvenient manner and having its inner end loose, so that the same canbe bent upward parallel with the edge of the bar, as shown. Thisprotector is preferably of leather, but may be of other material, andprevents marring as well as forms a pliable rest for the under side ofthe axle.

The construction that I have shown and ded scribed may be slightlyvaried without departing from the nature and principle of the invention.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

l. In a lifting-jack, a lifting-bar provided with a series of teeth orprojections on its opposite edges in combination with a step or resthaving engaging portions oppositely arranged for engaging theprojections, substantially as described.

2. In a lifting-jack, the combination with a lifting-bar having a seriesof projections on its opposite edges, of a step or rest consisting of abent strip formed with oppositely-arranged openings through which thebar passes and having surfaces at the opposite ends of the openings forengaging the projections, substantially as described.

3. In a lifting-jack, the combination with a lifting-bar havingprojections on its opposite edges, of an open step or rest, havingoppositely-arranged openings, the end walls at one end of the respectiveopenings being fashioned to correspond substantially with IOO IIC

615,809 I Y s that of the projections of the bar and the opposite endWalls being fashioned to engage the projections, substantially asdescribed.

4. In a lifting-jack, the combination with a lifting-bar having a seriesof projections on its opposite edges, of a rest or bracket looselyplaced on the bar and having diagonally-arranged portions to engage withtheprojections, and a flexible pad or strip secured to Vitnesses:

WILLIAM GOLVIN, Jr., JOHN B. BAXTER.

